Centrifugal casting



April 15 1924.

L. CAMMEN CENTRIFUGAL CASTING Filed NOV. 25. 1922 I Patented Apr. 192 4.

' To all whom it may concern."-

- uNiTEos A-rs PATENTfoFFicE.

won 01mm, or "New YORK, n. Y.'

omzrnrruonr. CASTING.

Application filed November-25, 1952. Serial No. eoaa'zs.

. Be 'it known that. I LEON 'CAMMEN, citizen of the United. states, and residing in the borough of Manhattan, in the county,

which are discontinuous, or whereof the.

outer surface is generated 'by a line moving so that. it is alternately approaching to, orv receding from, the axis of rotation to the first of these two categories belong such objects as split tubes, or castings being-arcs of a circle, or the like; totheisecpnd category belong bars, gears, and the ike.

In the illustrations: Y

Fig. 1 is asection through the mold in a plane normal to the axis of rotation;

Fig. 2 'is a section through a plane comprising the axis of rotation ina direction indicatedin Fig. 1 b A-B; i

Fig. 3, a section similar to that of 2, but in a direction indicated in Fig. 1 by 0-D. V

Attempts to cast centrifugally bars and gears are old, and for example A. E. Fay

' (Centrifugal casting, Iron Age, February 28, 1901) refers to theminan article more than twenty years old.. None of them 'proved to be successful for the following reason.

In all. of these attempts the 'mold was shaped 'all the way as shown in cross-section in Fig. 1, andmetal was supplied to i't -while' the mold was spinning. Before the metal can reach the-bottom of the mold 1, it encounters the. rapidly movingprojections 6, and the powerful blow-of the project-ionsfi against the stream of molten metal tends to scatter itin arather fine spray which, as has been found in centrifugal casting, chil1s .while it is in the air, falls back in the form of shot, and is only seldom remelted and fully incorporated into the metal of the casting. Because of this, what is known as cold shot, is produced in the casting, which means that the'casting in which case it is preferableto'make the 1 split along the plane AB, rather than contains particles of metal which are not homogeneously united .to the. rest of the metal, but have surfaces of cleavage dividing them therefrom. Such u castings are ,weak mechanically,'and in particularc'annot be used for further operations, such as rolling, drawing and forging, as is. well known to metallurgists.

The present invention solves this problem by giving the mold such a .construction spout does not immediately. encounter the partitions 6, but is spread between them gently, so as not to produce any scattering or splashing.

' that the metal as it is discharged'from the This can be'accomplished by adding to 1 the mold having a cross-section. shown in Fig. 1, the bottle-neck 2.3, shown in Fig. 2. The metal is discharged from the spout intothe smooth-borepart 2 of the bottle-neck, where there is nothing tocausei the metal to scatter or splash. From this, by the component of centrifugal forceacting in the case of liquids along the axis of the mold, the molten metal is propelled into the conical part 3 of the bottle-neck,-

and thence spreads between the projecting lugs 6. As shown in Fig. 2, the lugs-6 are made to' lie snugly against the cone of the bottle-neck some distance below the beginning ofthe conical shape 3',and if these I ends. are properly shaped, there is no splashing of the metal.

2 of the bottle-neck.

The cylindrical part may be omitted, in which case however there will be more tendency to splash, though even I there the splashing may be obviated by careful design of the end-s of the lugs 6, and by'giving the cone 3 a comparatively small angle of inclination.

It is also possible to omit the conical part 3 of the bottleneck, but in that" case there will be a heavy end plu of the size of the internal-bore of 2,'whic makes it possible to remove the casting only from the pouring end as a rule, this is not desirable.

In Figs. 1 and- 3, 7 indicates the casting or the metal spread between the lugs 6. This.

represents .lthecase of an'ingot' or plate casting." The casting of such artlcles as g ars'ditfers from this only by the facttfiat.

.more metal issupplied' to the mold, som'uch' in fact that the lugs 6 .are submerged,'and the teeth are connected with each other by a ring of metal cast over .the'lugs6.

The mold maybe cast 'splitin two parts, 7

a shape that the casting. should fall out freely as soon as the rotation of the machine ceased.

In the drawings, the bottle-neck is shown as being made separately from the part of the mold containing the lugs, as this appears to be cheaper and easier from a manufacturin' point of View. They can be however made in a single piece if desired.

In the drawings, the bottle-neck part is shown as having a smaller outer diameter than the main part of the mold., i. e., 1.

apply to centrifugal casting on horizontal I and inclined axes, the conditions producing splashing 1n casting on a vertical axis being different from those set forth in this speci fication, and therefore requiring other remedies to obviate them.

I claim:

1. A mold'for centrifugal casting consisting of two parts disposed along the axis of rotation, of which parts the one against which the metal of the casting is fed, has

a smooth internal surface, and the other part has projections of a shape suitable for the desired casting.

2. A mold for centrifugal casting consisting of two parts disposed along the axis of rotation, of which parts'the one against which the metal of the casting is fed, has a smooth internal surface of cylindrical shape, and the other part has projections of a shape suitable for the desired casting.

3. A mold for centrifugal casting consisting of two parts disposed along the axis'of rotation of which parts the one against which the metal of the casting is fed, has a smooth internal surface of the shape of a truncated cone contracting towards the pouring end, and the other part has projections of a shape suitable for the desired casting. Q

4. A mold for centrifugal casting consisting of two parts disposed along the axis of rotation, of which parts the one against which the metal of the casting is fed, has a smooth internal surface of a shape, in the division nearer the pouring end cylindrical, and in the division fdrther away from'the pouring end, of a truncated cone contracting towards the pouring end, and the other part has projections of a shape suitable for the desired castin Signed in New State of New York, November 24, 1922'.

LEON CAMMEN.

% ork, in the county and 

